Cold-rolled silicon steel wastewater treatment system
By designing a cold-rolled silicon steel wastewater treatment system that integrates emulsion wastewater, alkali oil wastewater and acid wastewater treatment, using multi-stage treatment and pH adjustment, the problems of large water quality differences and difficult treatment in traditional treatment are solved, and wastewater is realized The processing is simple and efficient.
Patent Information
- Application Number
- CN202420010893.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-03
- Publication Date
- 2025-02-21
- Estimated Expiration
- 2034-01-03
AI Technical Summary
In the traditional cold-rolled silicon steel wastewater treatment process, emulsion wastewater, alkaline oil wastewater and acid wastewater are difficult to process due to the large differences in water quality, and cannot be treated simultaneously in terms of pH or water quality, resulting in cumbersome subsequent treatment process.
A cold-rolled silicon steel wastewater treatment system was designed to integrate the treatment processes of emulsion wastewater, alkali oil wastewater and acid wastewater. Through multi-stage treatment, three wastewaters of different water quality were treated in the same system, respectively. The pH of the wastewater is adjusted and filtered to ensure the stability of the wastewater quality entering the post-treatment stage.
It effectively reduces the difficulty of wastewater treatment, simplifies the treatment process, reduces water quality fluctuations, improves the efficiency of wastewater treatment, and realizes simple and efficient treatment of cold-rolled silicon steel wastewater.
Smart Images
Figure CN222512849U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of industrial wastewater treatment, in particular to a cold-rolled silicon steel wastewater treatment system. Background Art
[0002] In the traditional cold-rolled silicon steel wastewater treatment process, the cold-rolled silicon steel wastewater often includes emulsion wastewater, alkali oil wastewater and acidic wastewater. The water quality of the wastewater varies greatly. During the treatment process, it is usually necessary to separately treat the above different wastewaters. The separate treatment of different wastewaters is often difficult, and the subsequent water treatment process will be more difficult due to the large fluctuations in water quality. Separate treatment of the three different wastewaters will also lead to insufficient utilization of water resources.
[0003] In addition, in the traditional cold-rolled silicon steel wastewater treatment process, since the emulsion wastewater, the alkali oil wastewater and the acidic wastewater are treated independently, the pH or water quality of each wastewater cannot be synchronized, resulting in the water quality or pH of the three wastewaters after treatment still cannot be unified, which makes the subsequent treatment process more cumbersome.
[0004] Based on the above problems, in order to further treat the cold-rolled silicon steel wastewater more conveniently and energy-efficiently, the present application proposes a cold-rolled silicon steel wastewater treatment system, which integrates the treatment processes of three different water quality wastewaters, namely the emulsion wastewater, the alkali oil wastewater and the acidic wastewater, and performs multi-stage treatment on the three different water quality wastewaters, so that the three different water quality wastewaters can be treated in the same wastewater treatment system, which effectively reduces the difficulty of wastewater treatment and simplifies the wastewater treatment process. In addition, in the present application, by adjusting the pH and filtering the emulsion wastewater, alkali oil wastewater and acidic wastewater respectively, the water quality of the wastewater entering the post-treatment stage is stable, the fluctuation of water quality is reduced, the difficulty of wastewater post-treatment is further reduced, and the efficiency of wastewater treatment is improved. Utility Model Content
[0005] To achieve the above objectives, the utility model is implemented through the following technical solutions: The utility model provides a cold-rolled silicon steel wastewater treatment system, including: an emulsion wastewater treatment unit, an alkali oil wastewater treatment unit, an acid wastewater treatment unit and a wastewater post-treatment unit;
[0006] The emulsion wastewater treatment unit is used to treat the emulsion wastewater to reduce the total oil content, COD, suspended matter content and total nitrogen content of the emulsion wastewater, and obtain primary wastewater with a pH of 6-9, and the primary wastewater is transported to the alkali oil wastewater treatment unit;
[0007] The alkali-oil wastewater treatment unit is used to receive the primary wastewater and treat the alkali-oil wastewater. The primary wastewater and the alkali-oil wastewater are combined in the alkali-oil wastewater treatment unit. The alkali-oil wastewater treatment unit is used to reduce the suspended matter content, COD and total oil content of the alkali-oil wastewater and obtain secondary wastewater with a total nitrogen content of less than 10 mg / L and a pH of 6-9. The secondary wastewater is transported to the acid wastewater treatment unit;
[0008] The acidic wastewater treatment unit is used to receive the secondary wastewater and treat the acidic wastewater. The secondary wastewater and the acidic wastewater are combined in the acidic wastewater treatment unit. The acidic wastewater treatment unit is used to reduce the suspended solids content, COD, total oil content and total iron content of the acidic wastewater, and obtain tertiary wastewater with a total nitrogen content of less than 5 mg / L and a pH value of 6-9. The tertiary wastewater is transported to the wastewater post-treatment unit;
[0009] The wastewater post-treatment unit is used to treat the tertiary wastewater and to obtain industrial water and industrial salt.
[0010] Preferably, the emulsion wastewater treatment unit includes a primary flotation treatment and a primary filtration treatment, wherein the primary flotation treatment is used to reduce the total oil content in the emulsion wastewater; and the primary filtration treatment is used to reduce the suspended matter content in the emulsion wastewater.
[0011] Preferably, the emulsion wastewater treatment unit further comprises a primary pH adjustment treatment and a primary biochemical treatment, wherein the primary pH adjustment treatment is used to adjust the pH of the emulsion wastewater to 6-9, and the biochemical treatment is used to degrade organic matter in the emulsion wastewater.
[0012] Preferably, the alkali-oil wastewater treatment unit comprises an alkali-oil wastewater regulating tank, and the alkali-oil wastewater regulating tank is used to mix the primary wastewater and the alkali-oil wastewater to obtain the first mixed wastewater.
[0013] Preferably, the alkali-oil wastewater treatment unit also includes a secondary pH adjustment treatment, a secondary flotation treatment and a secondary biochemical treatment, wherein the secondary pH adjustment treatment is used to adjust the pH of the primary mixed wastewater to 6-9; the secondary flotation treatment is used to reduce the total oil content of the first mixed wastewater; and the secondary biochemical treatment is used to degrade organic matter in the first mixed wastewater.
[0014] Preferably, the alkali oil wastewater treatment unit further comprises a primary mixing and flocculation treatment, and the primary mixing and flocculation treatment is used to flocculate the suspended matter in the first mixed wastewater and to precipitate the suspended matter in the first mixed wastewater.
[0015] Preferably, the acidic wastewater treatment unit comprises an acidic wastewater regulating tank, and the acidic wastewater regulating tank is used to mix the secondary wastewater and the acidic wastewater to obtain second mixed wastewater.
[0016] Preferably, the acidic wastewater treatment unit also includes a tertiary pH adjustment treatment, a secondary mixing and flocculation treatment, an ozone advanced oxidation treatment and a secondary filtration treatment, wherein the tertiary pH adjustment treatment is used to adjust the pH of the second mixed wastewater to 6-9; the secondary mixing and flocculation treatment is used to flocculate suspended matter in the second mixed wastewater and precipitate the suspended matter in the second mixed wastewater; the ozone advanced oxidation treatment is used to degrade organic matter in the second mixed wastewater, and the secondary filtration treatment is used to filter suspended matter and sediment in the second mixed wastewater.
[0017] Preferably, a primary inclined plate sedimentation tank is provided at the end of the emulsion wastewater treatment unit, and the primary inclined plate sedimentation tank is used to receive the wastewater treated by the emulsion treatment unit, and the supernatant of the wastewater in the primary inclined plate sedimentation tank is primary wastewater, and / or, a secondary inclined plate sedimentation tank is provided at the end of the alkali oil wastewater treatment unit, and the secondary inclined plate sedimentation tank is used to receive the wastewater treated by the alkali oil treatment unit, and the supernatant of the wastewater in the secondary inclined plate sedimentation tank is secondary wastewater.
[0018] Preferably, the wastewater post-treatment unit includes reverse osmosis treatment, final filtration treatment, resin softening treatment and evaporation crystallization treatment. The reverse osmosis treatment is used to obtain industrial water and concentrate the hardness ions in the tertiary wastewater; the final filtration treatment is used to filter the particulate matter in the tertiary wastewater; the resin softening treatment is used to adsorb the hardness ions in the tertiary wastewater; and the evaporation crystallization treatment is used to obtain industrial salt.
[0019] It can be seen from the above technical solutions that the utility model has the following advantages:
[0020] In the utility model, a cold-rolled silicon steel wastewater treatment system is provided, comprising an emulsion wastewater treatment unit, an alkali-oil wastewater treatment unit, an acidic wastewater treatment unit and a wastewater post-treatment unit; the emulsion wastewater treatment unit is used to reduce the total oil content, COD, suspended matter content and total nitrogen content of the emulsion wastewater, and obtain primary wastewater; the alkali-oil wastewater treatment unit is used to receive the primary wastewater and treat the alkali-oil wastewater to obtain secondary wastewater; the acidic wastewater treatment unit is used to receive the secondary wastewater and treat the acidic wastewater to obtain tertiary wastewater; the post-treatment unit is used to treat the tertiary wastewater; through the coordinated use of the above units, the cold-rolled silicon steel wastewater treatment system can realize the unified multi-stage treatment of the three wastewaters with different water qualities, avoid the separate treatment of the three wastewaters with different water qualities, simplify the treatment process, effectively prevent the problem of large fluctuations in water quality during the treatment process, and make the overall treatment process of cold-rolled silicon steel wastewater more concise and efficient. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.
[0022] Figure 1 This is a schematic diagram of the process of a cold-rolled silicon steel wastewater treatment system proposed by the utility model;
[0023] Figure 2 It is a specific flow chart of a cold-rolled silicon steel wastewater treatment system according to an embodiment of the utility model. DETAILED DESCRIPTION
[0024] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0025] As used in the present invention, the singular forms "a", "an" and "the" include plural objects, the term "or" is generally used in a sense including "and / or", the term "several" is generally used in a sense including "at least one", and the term "at least two" is generally used in a sense including "two or more". In addition, the terms "first", "second" and "third" are used for descriptive purposes only and cannot be understood as indicating or suggesting relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second", and "third" may explicitly or implicitly include one or at least two of the features. The term "proximal end" is usually the end close to the operator, and the term "distal end" is usually the end close to the patient. "One end" and "the other end" as well as "proximal end" and "distal end" usually refer to two corresponding parts, which include not only the endpoints. The terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral body; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal connection of the two elements or the interaction relationship between the two elements. In addition, as used in the present utility model, an element is arranged on another element, which usually only means that there is a connection, coupling, matching or transmission relationship between the two elements, and the connection, coupling, matching or transmission between the two elements can be direct or indirect through an intermediate element, and it cannot be understood as indicating or implying the spatial position relationship between the two elements, that is, one element can be in any position such as inside, outside, above, below or on one side of another element, unless the content clearly indicates otherwise. For those skilled in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.
[0026] Please refer to Figure 1 As shown, a cold-rolled silicon steel wastewater treatment system of the present embodiment includes: an emulsion wastewater treatment unit, an alkali oil wastewater treatment unit, an acid wastewater treatment unit and a wastewater post-treatment unit; the emulsion wastewater treatment unit is used to treat the emulsion wastewater, to reduce the total oil content, COD, suspended matter content and total nitrogen content of the emulsion wastewater, and to obtain a primary wastewater with a pH of 6-9, and the primary wastewater is transported to the alkali oil wastewater treatment unit; wherein the emulsion wastewater has a pH of 6-9, a total oil content of 1000-15000 mg / L, a COD of 3000-50000 mg / L, and a total nitrogen content of 50-80 mg / L; the primary wastewater has a pH of 6-9, a total oil content of less than 15 mg / L, a COD of less than 300 mg / L, a total nitrogen content of less than 30 mg / L, and a suspended matter content of less than 30 mg / L.
[0027] It is worth noting that the emulsion wastewater treatment unit has an emulsion wastewater regulating tank, which is used to receive and store the emulsion wastewater and make the emulsion wastewater treatment unit process wastewater with a flow rate of 10m 3 / h. In other alternative embodiments, the wastewater treatment flow rate may also be 12m 3 / h; it can be adjusted according to different working conditions, and this application does not make too many restrictions here.
[0028] The alkali-oil wastewater treatment unit is used to receive the primary wastewater and treat the alkali-oil wastewater. The primary wastewater and the alkali-oil wastewater are merged in the alkali-oil wastewater treatment unit. The alkali-oil wastewater treatment unit is used to reduce the suspended matter content, COD and total oil content of the alkali-oil wastewater and obtain secondary wastewater with a total nitrogen content of less than 10 mg / L and a pH of 6-9. The secondary wastewater is transported to the acidic wastewater treatment unit; wherein the alkali-oil wastewater has a pH of 8-14, a total oil content of 100-200 mg / L, a COD of 500-2000 mg / L, a total nitrogen content of 6-15 mg / L, and a suspended matter content of 200-400 mg / L; the secondary wastewater has a pH of 6-9, a total oil content of less than 15 mg / L, a COD of less than 50 mg / L, a total nitrogen content of less than 10 mg / L, and a suspended matter content of less than 50 mg / L.
[0029] It is worth noting that please refer to Figure 2 As shown, in this embodiment, a primary inclined plate sedimentation tank is provided at the end of the emulsion wastewater treatment unit, and the primary inclined plate sedimentation tank is used to receive wastewater treated by the emulsion treatment unit, and the wastewater supernatant in the primary inclined plate sedimentation tank is primary wastewater, and / or, a secondary inclined plate sedimentation tank is provided at the end of the alkali oil wastewater treatment unit, and the secondary inclined plate sedimentation tank is used to receive wastewater treated by the alkali oil treatment unit, and the wastewater supernatant in the secondary inclined plate sedimentation tank is secondary wastewater. The inclined plate sedimentation is a prior art, and this application will not be described in detail here.
[0030] In addition, the alkali oil wastewater treatment unit has an alkali oil wastewater regulating tank, which is used to receive and mix the alkali oil wastewater and the primary wastewater, and make the alkali oil wastewater treatment unit treat the wastewater flow rate of 50m 3 / h, in other alternative embodiments, the treated wastewater flow rate may also be 60m 3 / h; it can be adjusted according to different working conditions, and this application does not make too many restrictions here.
[0031] The acidic wastewater treatment unit is used to receive the secondary wastewater and treat the acidic wastewater. The secondary wastewater and the acidic wastewater are combined in the acidic wastewater treatment unit. The acidic wastewater treatment unit is used to reduce the suspended solids content, COD, total oil content and total iron content of the acidic wastewater, and obtain tertiary wastewater with a total nitrogen content of less than 5 mg / L and a pH value of 6-9. The tertiary wastewater is transported to the wastewater post-treatment unit; the wastewater post-treatment unit is used to treat the tertiary wastewater. treated and used to obtain industrial water and industrial salt; wherein the acidic wastewater has a pH of 1-7, a total iron content of 1000-10000 mg / L, a COD of 100-400 mg / L, a total nitrogen content of less than 5 mg / L, and a suspended matter content of 200-400 mg / L; the tertiary wastewater has a pH of 6-9, a total iron content of less than 0.6 mg / L, a COD of less than 30 mg / L, a total nitrogen content of less than 5 mg / L, and a suspended matter content of less than 20 mg / L.
[0032] Please refer to Figure 2 As shown, in this embodiment, the emulsion wastewater treatment unit includes a primary flotation treatment, a primary filtration treatment, a primary pH adjustment treatment and a primary biochemical treatment in sequence; the primary flotation treatment is usually a vortex flotation treatment, and the vortex flotation treatment is used to reduce the total oil content in the emulsion wastewater. Secondly, it can also be used to remove impurities such as colloids in the wastewater; the filtration treatment is used to reduce the content of suspended matter in the emulsion wastewater, and the suspended matter includes but is not limited to colloids, particulate matter, etc. in the emulsion wastewater; the primary pH adjustment treatment is: when the pH of the emulsion wastewater is higher than 9 or lower than 6 due to special working conditions, the emulsion wastewater is added with acid or alkaline solution to adjust the pH so that the pH of the emulsion wastewater is in the range of 6-9; the primary biochemical treatment is usually AO biochemical, which is used to degrade organic matter in the emulsion wastewater. It is worth noting that the working order of the above treatments can be adjusted according to different working conditions. In addition, the above technologies are all prior art, so this application does not make too many restrictions here.
[0033] Please refer to Figure 2As shown, in this embodiment, the alkali-oil wastewater treatment unit includes a secondary pH adjustment treatment, a primary mixing and flocculation treatment, a secondary flotation treatment and a secondary biochemical treatment; since the pH span of the alkali-oil wastewater is relatively large, and it is mixed with the primary wastewater to obtain the first mixed wastewater, in the alkali-oil wastewater treatment unit, the first mixed wastewater is continuously added with an acid or alkaline solution to adjust the pH of the first mixed wastewater, so that the pH of the first mixed wastewater is between 6 and 9; the primary mixing and flocculation treatment adds a flocculant to the first mixed wastewater, so that the suspended matter such as colloids and particulate matter in the first mixed wastewater is flocculated and precipitated; the secondary flotation treatment can also be a vortex flotation, which is used to reduce the suspended matter and total oil content in the first mixed wastewater, and the secondary biochemical treatment can be an aerobic biochemical treatment, which is used to degrade organic matter in the first mixed wastewater. The above technologies are all prior arts, and this application does not make too many limitations and redundant descriptions here.
[0034] Please refer to Figure 2 As shown, in this embodiment, the acidic wastewater treatment unit includes a three-stage pH adjustment treatment, a two-stage mixed flocculation treatment, a two-stage filtration treatment and an ozone advanced oxidation treatment; the acidic wastewater has a low pH value and is mixed with the two-stage wastewater to obtain a second mixed wastewater. In the acidic wastewater treatment unit, an acid or alkaline solution is continuously added to the second mixed wastewater to adjust the pH value of the second mixed wastewater so that the pH value of the second mixed wastewater is between 6 and 9; the two-stage mixed flocculation treatment adds a flocculant to the second mixed wastewater so that suspended matter such as colloids and particulate matter in the second mixed wastewater flocculates and precipitates; the two-stage filtration treatment can be sand filtration or filtration through a filter net to filter particulate matter or colloids in the second mixed wastewater, and the ozone advanced oxidation treatment is used to degrade organic matter in the second mixed wastewater.
[0035] In addition, please refer to Figure 2 As shown, the wastewater post-treatment unit includes reverse osmosis treatment, final filtration treatment, resin softening treatment and evaporation crystallization treatment and other treatment processes. In the embodiment mentioned in the present application, the tertiary wastewater is first subjected to ultrafiltration, and then subjected to primary reverse osmosis, secondary reverse osmosis and tertiary reverse osmosis in sequence for desalination. The produced water obtained from each stage of reverse osmosis enters the next stage of reverse osmosis. After the third stage of reverse osmosis, the produced water obtained is pure water. In addition, the concentrated water obtained from each stage of reverse osmosis is returned to the previous stage of reverse osmosis to continue the desalination reverse osmosis treatment, and the concentrated water from the first stage of reverse osmosis enters the two-stage chemical reaction for treatment.
[0036] It is worth noting that the two-stage chemical reaction is used for hardness removal, specifically for removing calcium and magnesium ions in the primary reverse osmosis concentrated water through sodium carbonate and sodium hydroxide. The two-stage chemical reaction is a prior art and this application will not go into details here.
[0037] In this embodiment, the concentrated water of the first reverse osmosis after the hardness is removed by the two-stage chemical reaction continues to be subjected to hardness removal tubular microfiltration and resin softening treatment for hardness removal, and finally undergoes a four-stage reverse osmosis treatment, and the produced water enters the second reverse osmosis for circulation treatment, and the concentrated water obtained by the four-stage reverse osmosis enters the second two-stage chemical reaction and silicon removal tubular microfiltration for further hardness removal and silicon removal treatment, and the concentrated water obtained after hardness and silicon removal enters the nanofiltration section, and the produced water obtained by nanofiltration enters the final reverse osmosis treatment; the final reverse osmosis treatment is high-pressure reverse osmosis, which can be used for reverse osmosis separation of concentrated water with higher concentration; the concentrated water obtained by nanofiltration enters the multi-effect evaporation section, and impure salts are obtained after the evaporation is completed; the produced water obtained by the final reverse osmosis enters the first reverse osmosis for further circulation treatment; the concentrated water obtained by the final reverse osmosis enters the evaporation and crystallization section for evaporation and crystallization, and the mother liquor obtained by evaporation and crystallization enters the multi-effect evaporation section to obtain impure salts; the solid obtained in the evaporation and crystallization section is high-quality sodium chloride salt.
[0038] It is worth noting that the evaporation and crystallization treatment mentioned in the present application can be processed by an MVR device, and the final reverse osmosis treatment can be processed by DTRO. The above are all prior arts. In addition, the processes mentioned in the above wastewater post-treatment unit are only specific processes of one embodiment of the present application. The processes can be adjusted according to different working conditions, and individual steps can be replaced by equivalents, such as using resin softening treatment to replace the two-stage chemical reaction in the present application for hardness removal. The above are all within the scope of protection of the present application, and the present application will not make too many restrictions and elaborations here.
[0039] In summary, in the utility model, a cold-rolled silicon steel wastewater treatment system is proposed, which integrates the treatment processes of three wastewaters with different water qualities, namely the emulsion wastewater, the alkali oil wastewater and the acidic wastewater. By performing multi-stage treatment on the three wastewaters with different water qualities, the three wastewaters with different water qualities can be treated in the same wastewater treatment system, which effectively reduces the difficulty of wastewater treatment and simplifies the wastewater treatment process. By adjusting and filtering the pH of the emulsion wastewater, the alkali oil wastewater and the acidic wastewater respectively, the water quality of the wastewater entering the post-treatment stage is stable, and the pH is always between 6 and 9, which reduces the fluctuation of water quality, further reduces the difficulty of wastewater post-treatment, and makes the overall treatment process of cold-rolled silicon steel wastewater more concise and efficient.
[0040] Finally, it should be noted that the above is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present utility model shall be included in the protection scope of the present utility model.
Claims
1. A cold-rolled silicon steel wastewater treatment system, used to treat cold-rolled silicon steel wastewater, characterized in that: include: Emulsion wastewater treatment unit, alkali oil wastewater treatment unit, acid wastewater treatment unit and wastewater post-treatment unit; The emulsion wastewater treatment unit is used to treat the emulsion wastewater to reduce the total oil content, COD, suspended matter content and total nitrogen content of the emulsion wastewater, and obtain primary wastewater with a pH of 6-9, and the primary wastewater is transported to the alkali oil wastewater treatment unit; The alkali-oil wastewater treatment unit is used to receive the primary wastewater and treat the alkali-oil wastewater. The primary wastewater and the alkali-oil wastewater are combined in the alkali-oil wastewater treatment unit. The alkali-oil wastewater treatment unit is used to reduce the suspended matter content, COD and total oil content of the alkali-oil wastewater and obtain secondary wastewater with a total nitrogen content of less than 10 mg / L and a pH of 6-9. The secondary wastewater is transported to the acid wastewater treatment unit; The acidic wastewater treatment unit is used to receive the secondary wastewater and treat the acidic wastewater. The secondary wastewater and the acidic wastewater are combined in the acidic wastewater treatment unit. The acidic wastewater treatment unit is used to reduce the suspended solids content, COD, total oil content and total iron content of the acidic wastewater, and obtain tertiary wastewater with a total nitrogen content of less than 5 mg / L and a pH value of 6-9. The tertiary wastewater is transported to the wastewater post-treatment unit; The wastewater post-treatment unit is used to treat the tertiary wastewater and to obtain industrial water and industrial salt.
2. A cold-rolled silicon steel wastewater treatment system according to claim 1, characterized in that: The emulsion wastewater treatment unit includes a primary flotation treatment and a primary filtration treatment. The primary flotation treatment is used to reduce the total oil content in the emulsion wastewater; the primary filtration treatment is used to reduce the suspended matter content in the emulsion wastewater.
3. A cold-rolled silicon steel wastewater treatment system according to claim 2, characterized in that: The emulsion wastewater treatment unit also includes a primary pH adjustment treatment and a primary biochemical treatment, wherein the primary pH adjustment treatment is used to adjust the pH of the emulsion wastewater to 6-9, and the biochemical treatment is used to degrade organic matter in the emulsion wastewater.
4. A cold-rolled silicon steel wastewater treatment system according to claim 1, characterized in that: The alkali-oil wastewater treatment unit comprises an alkali-oil wastewater regulating tank, and the alkali-oil wastewater regulating tank is used to mix the primary wastewater and the alkali-oil wastewater to obtain first mixed wastewater.
5. A cold-rolled silicon steel wastewater treatment system according to claim 4, characterized in that: The alkali oil wastewater treatment unit also includes a secondary pH adjustment treatment, a secondary flotation treatment and a secondary biochemical treatment, wherein the secondary pH adjustment treatment is used to adjust the pH of the first mixed wastewater to 6-9; the secondary flotation treatment is used to reduce the total oil content of the first mixed wastewater; The secondary biochemical treatment is used to degrade organic matter in the first mixed wastewater.
6. A cold-rolled silicon steel wastewater treatment system according to claim 4, characterized in that: The alkali oil wastewater treatment unit further includes a primary mixing and flocculation treatment, and the primary mixing and flocculation treatment is used to flocculate the suspended matter in the first mixed wastewater and to precipitate the suspended matter in the first mixed wastewater.
7. A cold-rolled silicon steel wastewater treatment system according to claim 1, characterized in that: The acidic wastewater treatment unit comprises an acidic wastewater regulating tank, and the acidic wastewater regulating tank is used to mix the secondary wastewater and the acidic wastewater to obtain second mixed wastewater.
8. A cold-rolled silicon steel wastewater treatment system according to claim 1, characterized in that: The acidic wastewater treatment unit also includes a tertiary pH adjustment treatment, a secondary mixed flocculation treatment, an ozone advanced oxidation treatment and a secondary filtration treatment. The tertiary pH adjustment treatment is used to adjust the pH of the second mixed wastewater to 6-9; the secondary mixed flocculation treatment is used to flocculate suspended matter in the second mixed wastewater and precipitate the suspended matter in the second mixed wastewater; the ozone advanced oxidation treatment is used to degrade organic matter in the second mixed wastewater, and the secondary filtration treatment is used to filter suspended matter and sediment in the second mixed wastewater.
9. A cold-rolled silicon steel wastewater treatment system according to claim 1, characterized in that: A primary inclined plate sedimentation tank is provided at the end of the emulsion wastewater treatment unit, and the primary inclined plate sedimentation tank is used to receive the wastewater treated by the emulsion wastewater treatment unit, and the supernatant of the wastewater in the primary inclined plate sedimentation tank is primary wastewater, and / or, a secondary inclined plate sedimentation tank is provided at the end of the alkali oil wastewater treatment unit, and the secondary inclined plate sedimentation tank is used to receive the wastewater treated by the alkali oil wastewater treatment unit, and the supernatant of the wastewater in the secondary inclined plate sedimentation tank is secondary wastewater.
10. A cold-rolled silicon steel wastewater treatment system according to claim 1, characterized in that: The wastewater post-treatment unit includes reverse osmosis treatment, final filtration treatment, resin softening treatment and evaporation crystallization treatment. The reverse osmosis treatment is used to obtain industrial water and concentrate the hardness ions in the tertiary wastewater; the final filtration treatment is used to filter the particulate matter in the tertiary wastewater; the resin softening treatment is used to adsorb the hardness ions in the tertiary wastewater; and the evaporation crystallization treatment is used to obtain industrial salt.